Method and apparatus for evaluating thread tensioning devices



Aug; 7,1945 F. A. DECKER, JR, ETAL 3 METHOD AND APPARATUS FOR EVALUATINGTHREAD TENSIONING DEVICES Filed Dec. 30, 1942 Tmw w N a m EEO W. W

A m} mp B Patented Aug. 7, 1945 METHOD AND APPARATUS FOR EVALUAT- INGTHREAD TENSIONING DEVICES Ferdinand A. Decker, Jr., and Paul G. WoodwardParkersburg, W. Va" assignors to American Viscose Corporation,Wilmington, DeL, a corporation of Delaware Application December 30,1942, Serial No, 470,652

8 Claims.

It is a common practice to wind yarns or strands oi filamentary materialfrom one package to another. For example, rayon filaments in the form ofa cake resulting from. collecting in a centrifugal spinning bucket arecommonly'rewound into cones or other sorts of packages, such as skeins,prior to subsequent treatment or be- !ore shipment. In passing to thepackage being wound, the filamentary bundle proceeds to suitabletraversing guides and tensioning devices in order to form a uniformpackage. Because of the conditions under which the filamentary materialis collected within the spinning bucket in the form of a cake, thewindings therein are frequently irregularly disposed and as thefilaments areunwound from the cake, there frequently occurs a tendencyfor the outer windings of the cake either to stick to the filamentsbeing withdrawn or to catch them; This tendency of the filamentarybundle to stick or catch upon the windings of the cake exerts a pull orforce resisting the withdrawal of the bundle from the cake whichexhibits itself in the 'form of in-' creased tension. This pull orresisting force, frequently reierred to as a pluck, may'at times besufiicient in magnitude to stretch the yarn along portions of its courseof travel where the increased tension is unable to become expended bytakin up slack with sumcient rapidity. In' addition, certain tensiondevices in which the filamentary bundle passes around curves tend tomultiply the pluck in the portion of the filamentary bundle extendingbetween the curved surfaces of the tension device and the package beingwound. In this manner, plucks which are of themselves quite insufilcientto stretch the yarn are frequently magnified by the tension devices tosuch an extent that stretching occurs. As is well known in the art,yarns which exhibit localized stretched conditions exhibit what aretermed shiners'f' which are particularly objectionable and noticeable infabrics made from the yarn.

'Heretofore, it has been impossible to compare and to evaluate thenumerous tension devices that are available or which may be devised withrespect to their tendency to multiply the pull or pluck which occurs inunwinding the rayon or other cake because of the irregular character andoccurrence of the plucks which occur throughout such a cake and whichcan neither be controlled nor reproduced. It is an object of theinvention to provide a device which will make it possible to impart toan unwinding yarn or the like a standard reproduceable pluckof anydesired magnitude. A further object is to providea method It may beprovided for permitting adjustment of desired character.

and apparatus for evaluating tension devices. Further objects andadvantages of the invention will be apparent from the drawing and thedescription thereof hereinafter.

In the drawing, illustrative of the invention.

Figure 1 is a perspective view' showing the standard pluck reproducingdevice associated with a tension device in a winding procedure, and

Figure 2 is an elevational view of a modified arrangement of the devicewith a winding apparatus.

As shown in Figure l, a package 2 of filamentary material, such as abobbin or cone, is placed proceeding from the package through a suitablev guide 5 to control ballooning, thence through the particular tensiondevice 8 it is desired to test or evaluate, then over a tensionresponsive pulley I and finally to a suitable wind-up device 8, such asa cone or bobbin winder which draws the yarn or the like through thevarious devices at a controlled rate of speed. 1

The tension measuring device may be of any As shown, it comprises a disk9 mounted for rotation by suitable clock-work (not shown) and arecording stylus Ill carried with the pulley I by a suitable resilientarm Ii having one end adjustably secured in a standard I! which with theclock-work mechanism may be supported upon a suitable base I3. Theresilient arm H which carries the stylus Ill and the pulley "I and isresponsive to the tension in the filamentary bundle may be in the formof a flat or ribbon-like spring whose width extends in a directionperpendicular to the drawing. A set screw the standard'and stylus sothat it may bear lightly against a recording chart II, which may takethe form of a smoked chart adapted to be marked by the mechanical actionof the stylus in scraping the coating therefrom. This adjustment of thestylus and standard permit the removal of the stylus from the chart bypivotal action about a vertical axis.

The standard pluck device comprises a suitable supporting bracket itwhich may be fastened to the winding machine, such as to the support Ifor the unwinding package 2, so that it will be in proximity thereto.The bracket It supports a vertical post i! from which there extends anarm is carrying a freely pivotable yoke I9 supv porting a freelyrotatable pulley 20, The vertical post I! is provided at its top with ashoulder yond its point oi contact with the package windlngs, therebypreventing the ballooning action of the yarn from throwing it over thefree end of the rod 2!. The cord 24 rides over the pulley II and .themagnitude of the pluck is controlled by varying the weight placed uponthe platform N. The two rods carried by the sleeve may be made such sineas to balance each other though this is not essential. The angularityand height oi the arm II with respect to the bracket it may be ad-.iusted by means of the set screw It.

In operation, the angularity oi the arm II is preferably adjusted sothat when the rod 22 is in contact with the package 2, the horizontalcourse oi ms cord it between the pulley it and rod 2; is approximatelyat right bearing against the windings oi the package. Rod 22 preferablyis arranged to extend in a direction substantially pe pendicular to theaxis of the package although it may be inclined at any desired anglebetween this direction and a direction parallel to the axis oi thepackage. By operating the winding machine with a package to be unwoundwhich is oi a uniiorm character, it will readily be seen that areproduceable. pluck can be obtained and the repetition of the windingunder substantially the same conditions with each of the tension devicesthat are to be tested will indieats which oi the tension devices is themost suitable ior the purpose. A comparison oi the records ll taken witheach tension device reveals at a glance which oi such devices appliesthe most uniform tension and multiplies the plucks the least.

angles to the rod I3-- Whereas the traveling filamentary bundle is shownin Figure l as proceeding from the tension device 8 up and over thetension responsive pulle'y I oi the recording instrummt and then down tothe winding machine I, this arrangement is not mentiai since, as shownin Figure 2, the yarn may proceed from-the tension device 0 over a loosepulley 21, down under, the tension responsive pulley l of the recordinginstrument and then up to the wind-up device I.

While preferred embodiments of the invention have been disclosed, it isto be understood that changes and variations may be made withoutdeparting from the spirit and scope of the invention as defined by theappended claims.

We claim: V

l. A device for evaluating tension devices comprising a supportingbracket, a post in the bracket, a member extending transversely oi andbeing pivotally mounted on the post, an arm extending irom the post, apulley pivotally mounted on the arm, and 'a fiexible strand fastened toone end of the member andextendlng over the pulley ior supporting acounterweight.

2. A device ior evaluating tension demos prising a supporting bracket, apos us mounted in the bracket, a substantially rigid rod extendingtransversely oi and being pivotally mountsdonthepost,anarmextendingiromtbe post, a pulley pivotally mmmted on the arm, and afiexiblestrandia'stenedtooneendoitherodandextendingoverthepullegandsupportinga 8. In combination, a woimdpackage oi filamentary material. a tension device, a tension responsivedevice, means for drawing at a controlled speed the filamentary materialirom the wound package through the tension device and the tensionresponsive device in succession, a member tangent to the outer windingsoi the package, and means for pressing the member with predeterminediorce against the package.

5. In combination, a wound package of diamentary material, a tensiondevice, a tension responsive device, means for drawing at a controlledspeed the iiiamentary material from the woimd package through thetension device and the tension responsive device in succession; asubstantially rigid member tangent to the outer windings oi the packagehaving extensions oi sufilcient length in opposite directions irom thepoint oi contact at an angle to the axis of the package to preventballooning oi the filamentary material with respect to the package iromthrowing the filamentary material around an end of the member, and meansfor pressing the member with predetermined force against the package.

6. A method of evaluating tension devices comprising the steps ofpassing a continuous filamentary material at a controlled speed from-asubstantially uniformly wound package, against a portion of the outerwindings oi which a smooth rigid member is pressed, in successionthrough the tension device to be evaluated and a tension responsivedevice.

7. In an apparatus for evaluating tension devices, a support, a woundpackage oi filamentary material carried by the support, a substantiallyrigid member tangent to the outer windings oi the package havingextensions in opposite directions from the point oi contact arranged atan angle to the axis of the package to prevent the filamentary materialfrom being thrown around an end oi the member by the ballooning oi thefilamentary material with respect to the package as it is unwoundtherefrom, said member being mounted pivoially on an axis substantiallyparallel to that of the package, and means for swinging the member aboutits pivot and ior pressing it witha predetermined force against thepackage.

8, In an apparatus ior'evaluating tension devices, a support, a woundpackage at filamentary material carried by the support, a substantiallyrigid rod tangent to the outer windings oi the package and extending inopposite directions iron: the. point of contact at an angle to the axisoi the package to prevent the filamentary material irombeingthrownaroundanendoitherodbyih'e ballooning oi the filamentarymaterial with respect to the package as it is unwoimd therefrom, saidrod being mounted pivotally on an-axis substantially parallelto that ofthe package, and means for winging the rod about its pivot and forpressing it with a predetermined ioroe against the FmDINAND A. DECKER,Ja. PAUL G. WOODWARD.

